If sent to the Third Shinobi War in fanfiction, Naruto's abilities would be crucial. His chakra reserves are vast, which means he could keep fighting for long periods. His ability to quickly learn new techniques could also be utilized. For instance, if he saw an enemy using a unique jutsu, he might be able to copy or modify it for his own use. His speed and agility, which he developed through his training, would allow him to dodge attacks and get into good positions for counter - attacks. Moreover, his strong willpower could inspire his comrades and make them fight more bravely.